MacViews: Use Cocoa folder icons in tree views.

chrome/browser/chrome_browser_main_mac.mm

Index: chrome/browser/chrome_browser_main_mac.mm
diff --git a/chrome/browser/chrome_browser_main_mac.mm b/chrome/browser/chrome_browser_main_mac.mm
index 4b8d76b269a6252cdd03e4704c27e214feb7f514..402793126143d6117d530fea64f86dfe16d98b5b 100644
--- a/chrome/browser/chrome_browser_main_mac.mm
+++ b/chrome/browser/chrome_browser_main_mac.mm
@@ -107,9 +107,11 @@ void ChromeBrowserMainPartsMac::PreMainMessageLoopStart() {
   // have the strings avaiable for localization.
   // TODO(markusheintz): Read preference pref::kApplicationLocale in order
   // to enforce the application locale.
+  resource_delegate_.reset(new ui::MacResourceDelegate());
   const std::string loaded_locale =
       ui::ResourceBundle::InitSharedInstanceWithLocale(
-          std::string(), NULL, ui::ResourceBundle::LOAD_COMMON_RESOURCES);
+          std::string(), resource_delegate_.get(),
+          ui::ResourceBundle::LOAD_COMMON_RESOURCES);
   CHECK(!loaded_locale.empty()) << "Default locale could not be found";
 
   base::FilePath resources_pack_path;